All posts tagged "Astronomy"

03/31/2014

A total lunar eclipse is well positioned for all the United States in April, but most people will have to set their alarms for the middle of the night to see it. The moon passes into the shadow of Earth and takes on a reddish hue overnight from April 14 to 15. The far northeastern US will see the eclipse at moonset, but for the rest of the continental US, the whole eclipse is visible. The partial phase, as our shadow begins to cover up the brightness of the full moon and then gives it back, lasts for about an hour on either side of the total phase. Totality for the Central time zone begins at 2:07 a.m. CDT and ends at 3:25 a.m. CDT, and for Mountain time is from 1:07 a.m. to 2:25 a.m. Pacific time has to wait until just after midnight, from 12:07 a.m. to 1:25 a.m. The moon officially reaches full phase during the eclipse on April 15 at 2:42 a.m. CDT.

An annular solar eclipse follows a few weeks later, on April 29; however, as it occurs over Antarctica, it will go largely unseen by humans.

With the return of spring, constellations such as Virgo have taken center stage. Fortunately, Virgo has a lot of action for stargazers this month. The reddish planet Mars is close to Virgo’s brightest star, Spica. Mars shines more brightly at magnitude -1.5. The Red Planet reaches opposition on April 8, rising at sunset and setting at sunrise.

02/11/2014

One of the more elusive members of our solar system to observe is the Zodiacal Light. Late February is a good time of year to try to spot this dust that lies in the plane of our solar system. This plane is also called the path of the ecliptic, and it’s where we find the planets as they journey around our sky. The reason February is a good time to spot the Zodiacal Light is that the ecliptic rises away from the horizon at a steep angle, allowing the light to rise up in a pyramidal shape. The thicker part of the Zodiacal Light will be near the horizon and the light will taper off as it climbs upward.

Look west an hour or two after dark on a moon-free night. There is no New Moon in February, but there is one on January 30 and March 1, which means both the beginning and end of February will have dark skies and will be a good time to search for the Zodiacal Light. Getting away from cities and light pollution is also essential.

With no New Moon in February, that means the Full Moon will fall midmonth, which it does on February 14, reaching 100-percent lit at 3:53 p.m. PST. This Valentine’s Full Moon will be accompanied by the star Regulus in Leo the Lion, just to the moon’s left. (Side note: As there is not always a New Moon in the short month of February, there is also occasionally no Full Moon. The next February without a Full Moon will be in 2018, which will give both January and March two Full Moons each, the second one in each of those months being a Blue Moon.)

01/02/2014

Venus has been a brilliant point of light in the west after sunset for a few months, but in January it disappears on its way to becoming a morning object. Say good-bye to it on January 2 when the crescent moon floats just above Venus before it joins the sun.

Jupiter will be the planet to watch in January, shining at magnitude -2.7 in the constellation Gemini. Jupiter reaches opposition on January 5, rising at sunset and setting at sunrise. On this date, use a telescope to see the volcanic moon Io emerge from behind Jupiter. The other three Galilean moons are already stretched out in a line on the opposite side of the giant planet, from Europa to Ganymede to Callisto.

On January 14, the moon and Jupiter come within about five degrees of each other. The moon will reach full phase the next night. January’s full moon, the Wolf Moon, occurs at 8:52 pm PST on January 15, just three hours after apogee, when the moon is farthest from Earth in its orbit. Therefore, January’s full moon is the smallest of the year.

12/03/2013

UPDATE: Comet ISON was largely swallowed by the sun as it passed our star on Thanksgiving. The debris that emerged at first has dissipated and the comet is no more. R.I.P. ISON.

The first days of December will reveal just how Comet ISON survived its close encounter with the sun. As you look for it in the west after sunset, the first thing you will spot is a light so bright that you think it must be a plane. Yet it’s not. That bright light in the southwest is Venus, shining at its peak brilliancy, magnitude -4.9. On December 5, the moon is just to the upper right of Venus. On December 6, Venus is 26-percent illuminated with a 41 arcsecond disk.

Comet ISON will be to the lower right of Venus in early December. The comet’s motion will be to the northwest, taking it toward the North Star, Polaris, which it will reach in January. As the comet rises higher in the sky it will grow dimmer as it leaves the sun. On December 20 both Venus and Comet ISON are about the same height above the horizon.

The comet may have had its closest approach to the sun on November 28, but its closest pass of Earth will be on December 26 when it gets within some 39 million miles from us.

Jupiter has been rising a bit earlier every evening in Gemini in the east. Watch Jupiter and the moon rise together on December 18. The moon has a couple notable dates before its meeting with Jupiter. On December 14 the moon and the Pleiades star cluster get close, on December 15 the moon enters the head of Taurus the Bull, and on December 17 the skies are lit by the full moon.

10/29/2013

Comet ISON continues to zip toward the sun, making
its closest approach on November 28. Until then, you can look for ISON on
November mornings in the southeast before sunrise in the constellation Virgo.
ISON will head toward Virgo’s brightest star, Spica, passing it on the mornings
of November 17 and 18. At the end of the week, look for ISON just to the right
of Mercury and Saturn. A tail, if visible, will extend back up toward Spica.
After it passes the sun it will enter northern skies during the early evening.
Its magnitude is still only in telescopic range, but observers hope that it
will be a binocular or naked-eye object by late in the month.

Another comet, Comet 2P/Encke, is currently brighter
than ISON. Encke should reach its peak brightness at around magnitude 7
(binocular range) by the end of November. On November 24, both the comets will
be visible in the same wide telescopic field of view (1 ¼ degrees apart) in
predawn hours.

On November evenings the winter constellations,
including Taurus and Orion, are rising in the east. Just behind them is Gemini,
where Jupiter is currently found. The giant planet stays in late evening skies
for much of fall. On November 21, look for Jupiter pairing with the moon as
they come over the eastern horizon.

In the west, Venus is still prominent as it shines
more brightly than any other natural object in the night sky except the moon.
The moon and Venus pair up on November 6 as they both float in front of the
Milky Way.

On November 3 a hybrid solar eclipse occurs, but in
order to see any part of it in the United States, you’ll have to be on the east
coast. Places such as the Florida coast
will see a slim partial eclipse, while totality will wait for the other side of
the Atlantic, crossing over the heart of Africa and ending as an annular
eclipse in Somalia.

Three meteor showers occur in the month of November.
The first meteor shower is the South Taurids, which peaks on November 4/5. The
next week is the companion North Taurids, which peaks on November 11/12. The
last and best known of the November meteor showers is the Leonids.
Unfortunately, this year the Leonids’ peak on November 17 coincides with the
full moon, which reaches 100-percent lit the same night.

(Comet
ISON has been glowing with a green gas as it nears Earth. Credit: John Chumack)

Kelly Kizer Whitt loves clean, clear, and dark skies. Kelly studied English and Astronomy at the University of Wisconsin-Madison and worked for Astronomy magazine. She writes the SkyGuide for AstronomyToday.com. You can follow her on Twitter at twitter.com/Astronomommy.

10/17/2013

Cold and dark conditions shouldn't stop you from camping during winter. Just be sure to pack the right stuff. Here are some suggestions to help you brighten the experience:

A good cook tent, like MOUNTAIN HARDWEAR's Hoopster, makes a warm hangout for up to six people. Its innovative design, in which fabric functions as frame, provides stability against high winds and inclement weather. If your crew is hardy, you can use the Hoopster, designed with a removable floor, as a sleeping shelter for four. $600

With the Tikka RXP, PETZL took its reactive-lighting technology and applied it to a smaller, lighter-weight headlamp. The glow automatically adjusts to the degree of darkness you're in, reducing glare and battery usage. Depending on the situation, your beam will be focused, wide, or medium. $95

Equipped with a radiant burner, a heat exchanger, and an internal pressure regulator, the MSR Reactor Stove impressed us with how quickly it got things boiling. In winter, splurge on the $30 hanging kit so you can suspend the stove in your (adequately ventilated!) tent. No more making the cook freeze outside. Choose a 1-, 1.7-, or 2.5-liter system. $170 to $200, depending on size

10/01/2013

A penumbral lunar eclipse can be a trick to see. Unlike a "regular" lunar eclipse, the moon never passes into the darkest part of Earth’s
shadow, and therefore the dimming of the moon is slight and difficult to
detect.

For those in the United States, a penumbral eclipse will
already have begun on October 18 as the full moon rises. The farther east you
are, the more likely it is that you’ll see a change in the Hunter’s Moon. The
event will end soon after moonrise.

Observers are eagerly awaiting the appearance of Comet ISON,
which will put on its best show in November and December. But for those who
want to get an early peek, get up before sunlight in mid-October and look
east-southeast. Regulus, the brightest star in Leo, and reddish Mars will be
just one degree apart on October 14, with Mars about one degree above and to
the left of Regulus. Use binoculars or a telescope to look the same distance
and direction above Mars to find Comet ISON.

08/28/2013

Fall's cooler evenings arrive with a cluster of planets in
the west at twilight. Venus, Mercury, and Saturn are joined by the moon early
in the month. Mercury was a morning object in August but has edged into the
evening sky for September.

Venus is a brilliant magnitude -4.0 and looks like a plane
with its landing lights on except that it doesn’t move. By September 5, Venus
is a degree and a half above the star Spica. To Venus's upper left is the
Ringed Planet Saturn, and to Venus's lower right lies Mercury. Because Mercury
is so low and in the fading light of sunset, it may take a while before you can
spot it. On September 7, a line consisting of Saturn, Venus, Spica, and Mercury
spans 40 degrees from the southwest to the west. In addition, a thin crescent moon
can be found below this line. The recently set sun will make it difficult to
catch all the objects, however.

On September 8, catch a pretty photo-op when the crescent moon
lies two degrees to the left of Venus, with Spica almost four degrees to
Venus’s lower right. The next night the moon is wide left of Saturn. Saturn and
Venus have been closing in on each other and will get to within three and a
half degrees on September 17. Saturn is in the constellation Libra above Venus,
while Venus lies in the constellation Virgo. On the next night, September 18,
the planets keep their distance but Venus crosses the border to join Saturn in
Libra. Following this date the planets start to drift apart.

07/30/2013

One of the best meteor showers of the year is the Perseids,
which peaks over the weekend of August 10/11 and into the 12th. From 50 to 100
meteors an hour is possible. Like most meteor showers, the Perseids produce
their best show before dawn, but the constellation Perseus rises after the sun
sets in the north-northeast, therefore any time of evening will still give you
decent odds of catching some meteors. This shower often produces fireballs and
swift-moving meteors and is courtesy of debris left behind by Comet
Swift-Tuttle.

For planet watchers, Venus is still eye-catching in the west
at sunset. It glides under the feet of Leo the Lion, heading toward Virgo. On
August 9, find the crescent moon is to the lower left of Venus after sunset. On
August 11, Venus crosses the border into Virgo, heading toward the
constellation’s brightest star, Spica, but the two won't meet until September.
The moon, however, visits Saturn and Spica on August 12, lying between them as
it shines at 35-percent lit.

07/03/2013

From epic sunsets to shimmering stars, the sky's natural displays of beauty can rival any fireworks show. Where's the best place to find an unpolluted blue view? We've compiled a list of the top five cleanest skies in America based on the American Lung Association's State of the Air Campaign (the findings are based on measurements of short-term particle pollution).

1. Asheville-Brevard, North Carolina

Take a bow, Tarheels — Asheville and Brevard take first place for the cleanest metropolitan area in the country for 24-hour particle pollution. The list of opportunities for breathing in all that clean air is deep and wide. Literally. Western North Carolina is home to nearly 50 named peaks above 6,000 feet. The Great Smoky Mountains are two hours away from Asheville and serve as a habitat for more than 60 species of mammals alone.

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